RJSATLBA
Well-known member
I've just started to consider installing solar panels. I'd appreciate comments on whether there any any particular considerations or pitfalls to avoid when one of the main uses will be charging the i3.
PV Installation Considerations
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Gonville
Well-known member
I found this forum a very useful intro into the whole discussion.
http://insideevs.com/category/solar-2/
Is very US centric when talking prices but you get a good idea.
Anyone know if there is a good. UK source?
This is a good forum but perhaps less definitive. More good background reading.
https://speakev.com/forums/power/
I will have PV but only 5 panels on my new place. It's a race between the builders and the builders. Currently the Germans are forecasting to finish before the Brits on the dates I have. ;-). There is a very good article on the US site basically saying do it now and power your current and future EV free for 25 years. No brainier.
I hope that's some help in starting your journey. Let us know here you go.
http://insideevs.com/category/solar-2/
Is very US centric when talking prices but you get a good idea.
Anyone know if there is a good. UK source?
This is a good forum but perhaps less definitive. More good background reading.
https://speakev.com/forums/power/
I will have PV but only 5 panels on my new place. It's a race between the builders and the builders. Currently the Germans are forecasting to finish before the Brits on the dates I have. ;-). There is a very good article on the US site basically saying do it now and power your current and future EV free for 25 years. No brainier.
I hope that's some help in starting your journey. Let us know here you go.
MikeS
Well-known member
Ive had my PV installation from almost 2 years and am very please with it. My roof faces SW so I get power produced from around 1300 to sunset. On a sunny afternoon with my 12 panels the system produces around 12kw. As long as you have a S to W facing roof then you should be fine. Plenty of choice with regards to the panels themselves. Just look to get ones that have a good warranty with regard to degradation. I also insisted on a 5 year warrant with the inverter as its one of the more expensive units in a PV install. Mine is made by SMA and they sell an extended warranty. Had to contact SMA with a problem with the ‘Sunny Beam’ monitor and they were excellent and resolved the issue easily - in fact there first response was to offer a replacement Sunny Beam, but that was not required. I also insisted on a 2 year installation warranty on the installation work which proved useful when the system flagged up a fault after a year owing to moisture ingress into the panel leads. All solved promptly by the installer. I used a local installer (the boss lives up the road from me) so that I was confident about follow up support. I rarely trust the larger companies.
MarkN
Well-known member
MikeS said:
Do you really mean 12kw, or do you mean 12kwh (kilowatt-hours)? One kilowatt of power per panel seems too high, but 12 kilowatt-hours over an afternoon seems more reasonable. I have have 20 panels on a roof that is three degrees off from facing due south, and I live in Colorado which is certainly a better location for solar than anywhere in the UK. My peak AC power production is 4 kilowatts and on a good day I get 30 kilowatt-hours of energy. My panels are about 14% efficient while the highest generally available efficiency panels are 21% so any panel producing one kilowatt would have to be quite large.
MikeS
Well-known member
Yes - 12 kilo watt hour - please excuse my earlier shorthand.
Bunter
Well-known member
RJSATLBA said:
I can't think of any pitfalls per say but there are obvious limitations. If it's going to be one of the main uses of the panels make sure you have a car usage profile which fits with solar generation. Mine doesn't but I charge off the panels whenever I can.
I would strongly advise getting a personal recommendation on fitters as I have heard of some sub-standard work. The i3 gives you remote control over charging but most PV systems do not give you remote monitoring of production. But you can get something aftermarket to do that if it helps (I use the OWL Intuition PV). If you can get an extended warranty on the inverter definitely get it, the panels themselves have to be warranted to qualify for the feed in tariff scheme (in the UK).
We have had a 4 kw array for 2.5 years; 4 kw was optimal at the time because of the feed in tariff structure. We produce on average 1000 kWh per kw of installation per annum (South UK). We face just east of south and with the standard 10 amp charger, on a good day it makes enough surplus to charge the i3 without drawing any grid power between about 09:00 and 15:00, which is 6 hours and not enough to fill the car if empty or nearly empty. Our house draws quite a high static load so that's something to consider.
There are 2 approaches to play with; if you wanted to get as much in the car as possible without drawing grid power you can change the charge rate in car (but not remotely) so that the demand curve matches the surplus curve. Or you can decide just to charge the car and use as much of the surplus as possible but don't worry about drawing grid power to fill in the deficit. When you look at the cost there's sod all difference I think between these too philosophies, so I chose the latter to avoid madness
Obviously if you get a level 2 charger you would have to have a very big array to produce enough surplus to charge without drawing grid power. I have had days when we have used 35 kWh of electricity which should have cost 13p per kWh but because the panels have produce 25 kWh of it and we've used it all it has only cost an effective 4p per kwh. In the UK what we use does not affect what we get paid by the Government to produce it.
Bill
We have had a 10KW Solar system for a few years now. The orientation is not ideal, but we don't have any shading and our yearly output is just under 14MWh. (~1360KWh per KW of panel) We get more sun here than the south of UK We intend to charge the i3 from the panels when practical, or otherwise draw back power we exported to the grid when necessary.
For live logging, I suggest pvoutput.org It is a free (donation preferred but not required) site with thousands of solar systems logged around the world. They have multiple methods of uploading data, see here for auto uploader details. If you have a weather system logged via wunderground.com you can integrate ambient temperature with pvoutput.
We intend to charge the i3 from the panels when practical, or otherwise draw back power we exported to the grid when necessary.For live logging, I suggest pvoutput.org It is a free (donation preferred but not required) site with thousands of solar systems logged around the world. They have multiple methods of uploading data, see here for auto uploader details. If you have a weather system logged via wunderground.com you can integrate ambient temperature with pvoutput.
RJSATLBA
Well-known member
Thanks to all for the feedback.
I'm retired so my comings and goings don't follow a daily pattern, some days I'd probably be able to get a fairly good charge from thr PVs using a low charge rate but on others I would probably end up using some REx if I tried to make do without increasing the charge rate to draw from the grid.
Another thought has occurred, might it still make sense to switch to Economy 7 and charge overnight, it looks as if the cost would be less than the feed in tariff and the environmental contribution from the PVs would be the same whether it goes into the i3 HV or into the grid.
I'm retired so my comings and goings don't follow a daily pattern, some days I'd probably be able to get a fairly good charge from thr PVs using a low charge rate but on others I would probably end up using some REx if I tried to make do without increasing the charge rate to draw from the grid.
Another thought has occurred, might it still make sense to switch to Economy 7 and charge overnight, it looks as if the cost would be less than the feed in tariff and the environmental contribution from the PVs would be the same whether it goes into the i3 HV or into the grid.
Bunter
Well-known member
RJSATLBA said:
When I did the maths on what I thought we would use, switching to Economy 7 saved a little but not masses because the daytime rate is more expensive. You ought to get a usage monitor to get a feel for what you are using and when, then you'll be better informed to judge whether Economy 7 makes sense.
Bill
Gonville
Well-known member
Just had a quote for £8k for a 10 panel 3kw system. Includes 10 year warranty on bits and 20 year on the panels. Inclusive device for switching output to immersion.
Seems like a bit much.
Seems like a bit much.
ultraturtle
Well-known member
That's about $4.50 per watt US, which is what it costs around here for a quality system (SMA inverter and name brand mono crystalline panels) before federal and other incentives.Gonville said:
Gonville
Well-known member
I think that is for a multi? crystal 300w per panel Benq. Suspect there is about 25% profit margin in there somewhere. I've been quoted £3k for a 5 panel system on a new build - trouble is I have no figures for output on that one.
CompuMagic
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- Feb 23, 2014
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I am in the process of preparing to install a 20kW system, which is huge, and will basically cover my entire roof. I already have a 9.6kW Leviton EV charger that I installed in garage (about $1,000 self-installed and bought on Amazon), but no EV or PHEV at this point (I have been driving an Escape Hybrid SUV for 10 years in October, and if I drive the speed limit I still get from 31 to 36mpg). My system will be grid-tied and use 64 e-20 327w SunPower panels, 64 p400 SolarEdge optimizers, and two SolarEdge 10kW inverters.
8k Pound for 3 kW, that is a very high price. Here in Germany we pay about 1.400 Euro ( 1.130 Pound ) per kW ( without tax, which we get back ) for a 10 kW System.
Make it not too small, prices are much better for bigger installations. I will fill my roof east and west with 16-20 kW in a few weeks.
@CompoMagic
I am considering Solaredge too, if I find someone to install it. Want to use the 600W optimizers for 2 panels each.
Why 2 x 10 kW, price is much better if you use 1 x 17 kW. And you hardly loose any power with some undersizing like that, maybe 1-2%.
Frank
Germany
Make it not too small, prices are much better for bigger installations. I will fill my roof east and west with 16-20 kW in a few weeks.
@CompoMagic
I am considering Solaredge too, if I find someone to install it. Want to use the 600W optimizers for 2 panels each.
Why 2 x 10 kW, price is much better if you use 1 x 17 kW. And you hardly loose any power with some undersizing like that, maybe 1-2%.
Frank
Germany
Gonville
Well-known member
That's what I thought. Unfortunately I have only small roof and 10 panels is the max I think on the south facing side. Are solar edge the best?
Solaredge has an advantage particularly if you have shading, of which I have a lot - trees, neighbouring buildings, chimneys, dormer. For a 3 kW installation in full sun I wouldn´t bother.
Do you have a pic of your roof?
Frank
Do you have a pic of your roof?
Frank
MikeS
Well-known member
Mine is a 3kw rated system with 12 panels and cost 11k but that was with the previous higher payback rates. The device to automatically switch to the immersion is useful but costs by itself about £500. So I would think that £8 is a bit much for a UK system.
CompuMagic
Well-known member
- Joined
- Feb 23, 2014
- Messages
- 66
fdl1409 said:
In USA residential has split single phase 240v
Gonville
Well-known member
Picked this up from the speakEV forum. So my £8k quote is similar and near the top end.
https://speakev.com/threads/a-shadegreener-free-solar-or-bespoke-install-bristol.1835/
Paul Morris on speakEV said:
https://speakev.com/threads/a-shadegreener-free-solar-or-bespoke-install-bristol.1835/
RJSATLBA
Well-known member
Thanks for all the input to date, just had the first survey and very impressed with the company, seemed very thorough, took almost 2 hours but no sales push and no gimmicks.
I've already had a 32A BrGas/Polar wallbox installed (yes I know, people like me will be part of the reason why OLEV have suspended the grants because they've been paying out on installations that aren't being used and therefore suspect fraud!) but my intention was to charge at the 'standard' rate for the sake of battery life whenever time allowed as my understanding is that the rate of charge is determined by in-car settings, subject to the maximum available from whatever it is connected to.
With solar panels in mind, under the UK FIT feed in tariff regime, my understanding is that I'll get the most cost-effective outcome if I can set a low charge rate that will use as much of my excess generation as possible but no more. Can anyone tell me the lowest rate of charge that can be set?
I've already had a 32A BrGas/Polar wallbox installed (yes I know, people like me will be part of the reason why OLEV have suspended the grants because they've been paying out on installations that aren't being used and therefore suspect fraud!) but my intention was to charge at the 'standard' rate for the sake of battery life whenever time allowed as my understanding is that the rate of charge is determined by in-car settings, subject to the maximum available from whatever it is connected to.
With solar panels in mind, under the UK FIT feed in tariff regime, my understanding is that I'll get the most cost-effective outcome if I can set a low charge rate that will use as much of my excess generation as possible but no more. Can anyone tell me the lowest rate of charge that can be set?
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